What they're used for: Opioids are used to treat acute pain related to surgery and other medical procedures, as well as for persistent (chronic) and breakthrough pain that is moderate to severe. Persistent pain is usually treated with long-acting opioids that are released into the body slowly and control pain for long periods of time. You take them around-the-clock on a regular schedule, whether or not you are feeling any pain at the time. If there are episodes of breakthrough pain, a second short-acting opioid may be prescribed as well. Short-acting opioids work more quickly and do not stay in the body for as long a time. Opioids are sometimes taken in combination with non-opioids.

How they're taken: Opioids are usually by mouth, in pill or liquid form. Other forms include:

bandage-like skin patches that release the medication for a few days at a time

lozenges or suckers placed inside the cheek or under the tongue

patient-controlled analgesia pump, which allows you to push a button to give yourself a dose of pain medicine through a small needle placed under the skin (subcutaneous) or into a vein (intravenous)

rectal suppositories, which are capsules or pills placed inside the rectum so the medicine can dissolve and be absorbed into the body

Severe itching, skin welts or rashes, and trouble breathing all can be signs of a serious allergic reaction. Stop taking the medication right away and call your doctor.

Additional information:

Before taking opioids, tell your doctor whether you are taking sleep aids, tranquilizers, or any other medications that make you sleepy, and if you drink alcohol.

Over time, you may find that a certain opioid does not relieve your pain as well as it once did. This simply means that your body is becoming tolerant to the medication, not that you are addicted to it or that you are "weak" or not tough enough. You may need a higher dose, a different medication, or perhaps a second medication added to your treatment plan.

Do not stop opioid treatment abruptly without your doctor's guidance. When opioids are no longer needed, your doctor will taper down the dose gradually so that your body can adjust over time.